Method of lining curved track



. 3,165,073 METHQD 9F LENING CURVED TRAQK Weltzin B. Blix, South lviilwauiree, and 30hr: R. i lushrner, Milwaukee, Wis., assignors to Nordberg Manufacturing Company, Milwaukee, Win, a corporation Wisconsin Filed July 28, 1958, Ser. No."751,199

9 Claims. (Cl. 104-45) turbing the previous readings or corrections.

Another object is a method of the above type that, while it is not mathematically perfect, nevertheless, is easyand accurate.

Another object is a method of curve lining which may be performed or carried'out by no more than two people.

Another object is a method of lining curves of track which may :be applied to align an entirecurve or a part of a curve, or to merely check a curve or any part of it to see if lining is necessary.

Another object is a method of lining curved track which has the benefit of ease, simplicity and accuracy without the burden of precision calculation. 7

Another object is a method of curve lining which is foolproof and eliminates practically all operator error.

Other objects will appear from time to time in the ensuing specification and drawings in which: 1

FIGURE 1 is adiagrarnmatic plan 'view of a curve and the lining procedure; 1

FIGURE 2 is a diagrammatic plan view of a portion of the curve in FIGURE 1 on an enlarged scale showing one step of the method; and i FIGURE 3 is a graph used in the method.

In FIGURE 1 a curved section of track is shown in plan between two tangent sections A and B. The curve may be considered as made up 'of three parts or sections; For example, considering the lining procedure or method as starting on the straight section A and moving around the curve to the straight section B in the direction of the arrow, an incoming spiral C decreases in radius from the straight section A to a body section D of the 'curve, which has an approximately constant radius, and an outgoing spiral E having an increasing radius leads to the straight section B. We have shown division markers'ltl, 12, 14 and 16 between the various sections which are for "purposes of illustration only and, in reality, are imaginary.

The method involves the use of a reference line which may be a tension Wire or otherwise. The reference line is moved along or around the curve either continuously or in uniform steps to establish what we shall refer to as the actual ordinates. A mechanism which may be used to establish this reference line or wire is shown in detail in copending. application Serial No. 750,144, filed United States Patent M 3,lfi5,073 Patented Jan. 12, 1965 July 22, 1958, now Patent No. 3,050,015 issued August 21, 1962 and we have schematically or diagrammatically shown this mechanism in FIGURE 2. For example, it might include rear and frontwheeled buggies 18 and 29 and an intermediate or detector buggy or wheeled car 22. The buggies or cars have a reference line coordinating mechanism which tensions the wire between the front and rear buggies. For example, the wire is indicated at 24 and we prefer that the wire be tensioned but otherwise free between the front and rear buggy. Suitable spacers may be disposed between the three buggies to keepthem in a predetermined relative longitudinal spacing while the entire assembly is moved around the curve. As for spacing we might position the front and rear buggies 120 apart with the intermediate buggy 20' forward of the rear buggy. But this is merely an example and any other suitable spacing may be used.

It should be understood that the front and rear'buggie are constructed to-establish the reference line 24 a predetermined lateral distancefrom either one rail or the other which is used as the line rail. Thus, on tangent track the reference line 24 will be preciselyparallel to the track or the line rail but will be out-board of it, either on one side or'the other, a predetermined distance at all points'between the end buggies. But in moving around a curve the reference line 24 will remain straight and tensioned and will cross the are of the curve as .a chord. We prefer that the reference line or Wire '24 be disposed on the inside of the curve or outboard of the inner rail so that it will clear the intermediate buggy or track liner-22 at all times. However, it might 'be outboard of the superelevated rail under certain conditions or situathe actual lining operation should cease and the mech'-' tions. In fact, the reference line might be disposed between the rails, either equidistance between them or closer to one than the other. Ordinarily, in curve lining the referencing rail is the outside rail. The intermediate buggy or car 22 is suitably constructed to detect the lateral distance of the reference line 24 from the line rail adjacent the intermediate car. For example, We diagrammatically indicate a detector or sensing mechanism at 26. We may also provide a track liner'ZS for shifting the track laterally desired amounts.

The track liner may be the type shown in US. Patent 2,926,616, issued March 1, 1960, or it might be otherwise. The detector or target car 22 may fi't under the track liner, as shown in FIGURE 2, or it might be otherwise.

If the assembly is being used to line straight or tangent track and a curve comes up, the mechanism should be stopped at a point a short distance away from where eye observation indicates the curve starts. At this point anism should be moved around the curve sensing or taking ordinates or any other suitable data without actually lining. The assembly may be moved in equal steps around the curve taking ordinates while the buggies are maintained in their spaced longitudinal relation and the reference line is maintained an equal distance from the line rail at the front and rear buggies. we might move the assembly and reference line in steps equal to the length of'a rail, for example 39 feet, or it might be any suitable length. The shorter the individual For example,

' around the curve.

steps,- the more accurate the results. Maximum accuracy will be obtained if a graph is mechanically produced at the target car as-the assembly is continuously moved At each stop between steps the detector or sensing mechanism establishes the diiference between the position of the reference line adjacent the intermediate car and track liner and the predetermined lateral distance previously set at the front and rear buggies.

A typical procedure is shown in FIGURE 1 and the reference line 24 is schematically moved in steps around the curve andordinates or variations taken at each step. We prefer to observe and record ordinates since this is accurate and simple, however, any function of the curve which is a 'measure of curvature could be used, for

' plot the steps or stops which, in this case, are graduated in rail lengths, for convenience.

V The ordinate scale or vertical axis is divided in tenths of an inch. For example; division 5 on the vertical axis is 5A0 of an and from and We provide live equal graduations, each of which is a tenth of an inch.

.T he assembly may be. stopped at each of the stations and the actual ordinate directly measured or sensed and theniplotted'on the graph. For example, at station 3 the ordinate was measured and plotted as slightly more than 1 of an inch. At station 2 it was of an inch, and so'forth. yVe prefer, for simplicity, that the assembly be stopped only at each station and the ordinate read and plotted, but it might be more or less often. We might add that the more often the assembly is stopped and the shorter the steps are, the more accurate the results. However, we have found that steps of a rail length each are sufficiently accurate. i

The assembly is moved in uniform steps around the curve untilstraight track or tangent section B is reached and the actual ordinates areplotted at each station. In

the example shown in FIGURE 3 it will be noted that tWenty-fivesuch stops or rail lengths are in the curve. Nexbthe actual ordinates may be connected by lines, shown as broken lines in FIGURE 3, so that a jagged curve, designated A.O. (Actual Ordinates) is acquired. Actually, connecting the plotted actual ordinates is not necessary but it may be done for convenience. The operator may then freehand an average smooth curve, designated D.O. (Desired ordinates) and shown as a solid line in FIGURE 3, through the plotted actual 0rdinates. The free hand curve D.O. tends to average out the irregularity of the A0. curve and represents the desired ordinates; The more nearly the curves match,

the less'actual track movement or shifting required.

. After the D.O. curve has been established, the lining assembly and the reference line is moved back to where the original measurements started and is again moved in steps around thecurve. At each stop or between steps the desired ordinate D.O, corresponding to the D.O.

curveis taken from the graph and the track shifted later-.

ally until the actual ordinate equalsthe desired ordinate for that station or stop. The particular method or apparatus for shiftingthe track laterally to bring it to the less than the steps taken during recording to improve in FIGURE 3 the horizontal axis has been numerically graduated into rail lengths and subdivided into quarters so that sensing and recording of the actual ordinates may be in rail length steps but lining may be in quarter rail length steps. However, any suitable relationship may be used.

During the first pass around the curve when the actual ordinates are read with stops at each rail length or otherwise, we find it convenient to number the joints or stops with colored crayon, for example, on the ends of the ties, to correspond to the numerical designations on the horizontal axis of the graph so that during the subsequent lining operation the reference line may be positioned precisely at the same points or stops Where the actual ordinates were determined and uniform submultiples of them.

It should he noted in FIGURE 3 that the graph is provided wi h five units or graduations representing H of an inch of negative ordinate, and We find this particularly advantageous since negative ordinates quite often occur generally in the area where the tangent track A joins the incoming spiral C, for example generally at the division marker It).

it should be noted in the FIGURE 3 graph that the plot of the ordinates corresponds to the incoming spiral C, the body D of the curve, and the outgoing spiral E; the incoming spiral C having increasing ordinates from the zero station to approximately rail length station 12; the body of the curve D having approximately constant ordinates from rail length station 12 to approximately rail length station 16; and the outgoing spiral E having decreasing ordinates from approximately rail length station 16 to approximately rail length station 25.

The use, operation and function of the invention are as follows:

We provide a simple, but suiliciently accurate and highly practical method of lining railroad curves, which does not require skilled operators. We use a longitudinal reference line and the particular assembly for establishing the reference line is not important. The point is that the reference line, which is a constant length during the operation, is moved either in steps or continuously around the curve, and ordinates or any factor indicative of variation in curvature are recorded. While we have referred to and illustrated the method as a step by step procedure. it might be continuous, Also, we could graphically and mechanically record the actual ordinates or other data, for example, on a moving tape with a stylus rather than manually recording the actual ordinates in a step by step procedure. However, we prefer the particular method illustrated and described because of its simplicity and accuracy which, while it is not mathematically erfect, nevertheless, is precise and accurate enough for all practical purposes.

If the plotted actual ordinates indicate that a particular curve is sufiiciently smooth after the sensing steps, the

track lining steps may be dispensed with. In this sense, the method may be used to determine whether or not a curve should be lined.

It should also be understood that any portion of a curve may be sensed and lined or merely sensed if it is not desirable to line or sense the entire curve. We have shown and illustrated the method as involving the steps of sensing, recording and adjusting the ordinates but it might be the. deflection angles. We prefer to use ordinates since they are more accurate, easier to work with, and more easily obtained.

In actual practice it has been found desirable to read the actual ordinates and determine the desired ordinates for the incoming and outgoing curve spirals but not for the body of the curve. The method has the advantage that if a condition should be found within the body of a curve indicating that the curve is compounded, meaning that it becomes sharper or flatter, then it may be necessary to stop and take ordinate readings to line that portion of the body. The point is that it is possible to stop lining and start taking or sensing ordinate readings while the curve is being lined to determine the desirable ordinates by the graphic method and to line to them. In this sense the method can be stopped, started or discontinued or resumed at any time during the procedure without affecting its accuracy or efiiciency.

If more accuracy is desired, then it is only necessary to line the curve a second time, using the same desired ordinates. Each successive relining brings the actual final ordinates closer to the desired ordinates. only one lining is necessary.

It should be noted that the method is applicable to tangent track as well as curves. For example, it might be used in approaching or leaving a fixed structure, such as a bridge or any structure or point where it is not desirable to line the track because unspiking or some other undesirable condition might be necessary. In this case it may be advisable to take or record actual ordinates up to and away from the bridge and then to bend a very slight curve from the average tangent both into the bridge and. away from it.

While We have stated that the desired ordinate is held constant or approximately constant in the body of the curve D, it may be varied somewhat. For example, if the ordinate of the curve body D is too small and we build up to a large inward throw toward the curve center so that in lining the curve we are attempting to flatten it, we may simply back up a station or two and increase the desired ordinate reading for the body of the curve and then continue lining. The reverse of this is also true. If the particular desired ordinate for the curve body builds up to an excessive outward throw away from the center of the curve, this indicates that we are trying to sharpen the curve too much. In this case, we may merely back up a few rail lengths or stations and reduce the desired ordinate a small amount and continue lining. In effect, this puts a very minor but entirely unobjectionable compound in the curve.

While we have shown and described the preferred form and suggested several variations of our invention, it should be understood that numerous additional modifications, changes, alterations and substitutions may be made without departing from the inventions fundamental theme. We, therefore, wish that the invention be unrestricted except as by the appended claims. In particular, we wish it to be understood that, our method can be carried out with a reference line established by any suitable means. The reference line may, for example, be maintained or established by projecting a light beam in predetermined relation to a rail. Suitable means may be employed to take the place of the mechanical contact or element 26. The sensing element or means to be employed in such case will be a light sensitive member adapted to be aligned with the projected beam of light.

We have mentioned a tensioned wire and a light beam, and we may also use sound waves or a radio beam as the reference line. It should therefore be understood that the particular means or apparatus for establishing the reference line is not important. Whereas we have shown buggies, movable along the track, to which a tension wire may be secured, it will be understood that the tension wire may be secured directly to the track or in predetermined relation to the track by any other suitable means.

We claim:

1. A method of lining curved track, including the steps of establishing a reference line between spaced front and rear stations on the track, positioning the reference line in predetermined lateral relation at both stations from one of the rails as the line rail, establishing an intermediate station between and in predetermined spaced relation to the front and rear stations, moving the stations, as a group, around the curve in generally equal In most cases Y longitudinal steps, while maintaining their relative spacing, sensing at each step a variation, if any, indicative of the lateral distance of the reference line from the line rail to the previously established predetermined lateral relation at the intermediate station to establish a series of actual variations, plotting a two dimensional graph with the actual variations as one dimension and the longitudinal steps as the other, aver-aging a curve through the actual variations, taken as a group, to establish a series of desired variations, repeating the step of moving the stations, as a group, around the curve in generally equal steps, and shifting the track laterally at each step, where necessary, at the-intermediate station to establish the desired variation from the reference line on the track.

2. The method of claim 1 further characterized by and including the step of making the length of the steps in moving of the stations around the curve during the shifting operation generally equal to the length of the steps used 'in initially moving the stations, as a group, around the curve during the sensing operation.

3. The method of claim 1 further characterized by and including the step of using the superelevated outer rail as the line rail.

4. The method of claim 1 further characterized by and around the curve in generally equal longitudinal steps with stops in between .while maintaining their relative longitudinal spacing, sensing the difference, if any, between the lateral distance of the reference line from the line rail to the previously established predetermined lateral distance at the intermediate station at each stop to establish a series of actual ordinates, plotting a two dimensional graph with the actual ordinates as one dimension and the longitudinal steps as the other, averaging a curve through the thus plotted actual ordinates to establish a series of desired ordinates, repeating the step of moving the stations, as a group, around the curve in generally equal steps and stopping at least in approximately the same places as before, and shifting the track laterally, where necessary, at each stop to position the intermediate station at a distance from the reference line equal to the predetermined distance plus the desired ordinate for each stop.

6. The method of claim 5 further characterized by and including the step of moving the stations, as a group, during sensing, in steps equal generally to a rail length.

7. The method of claim 5 further characterized by and including the step ofmaking the length of the steps during shifting a submultiple of the length of the steps used during sensing.

8. A method of lining curved track, including the steps of establishing an otherwise free rectilinear reference line between spaced front and rear stations on the track, using one rail as a line rail, positioning the reference line in predetermined lateral relation at each station from the line rail so that all points between the stations and the reference line will have a determinable lateral relation,

to the line rail, establishing an intermediate station between and in predetermined longitudinal spaced relation to the front and rear stations, moving the stations, as a group, around a curve while maintaining their relative spacing, sensing the difference in the lateral relation of the reference line to the line rail to the previously established relation to establish a series of actual variations, plotting a two dimensional graph with the actual variations as one dimension and a representation of the curve length as the other, averaging a curve through the actual variations to establish a series of desired variations, re-

peating the step of moving the stations, as a group, around the curve, and shifting the track laterally, Where necessary, to position the intermediate station at the desired variation from the reference line.

9. The method of claim 8 further characterized by and including the step of positioning the reference line an equal lateral distance from the line rail at the front and rear stations.

References Qited in the file of this patent UNITED STATES PATENTS e'atfenschinidt May 39, Funk Jan. 3, Bienfait Oct. 25, Petry Nov. 28, Piechtcr May 1'0, McCormick Dec. 6,

Talboys Aug. 2 

1. A METHOD OF LINING CURVED TRACK, INCLUDING THE STEPS OF ESTABLISHING A REFERENCE LINE BETWEEN SPACED FRONT AND REAR STATIONS ON THE TACK, POSITIONING THE REFERENCE LINE IN PREDETERMINED LATERAL, POSITIONING THE STATIONS FROM ONE OF THE RAILS AS THE LINE RAIL, ESTABLISHING AN INTERMEDIATE STATION BETWEEN AND IN PREDETERMINED SPACED RELATION TO THE FRON AND REAR STATIONS, MOVING THE STATIONS, AS A GROUP, AROUND THE CURVE IN GENERALLY EQUAL LONGITUDINAL STEPS, WHILE MAINTAINING THEIR RELATIVE SPACING, SENSING AT EACH STEP A VARIATION, IF ANY, INDICATIVE OF THE LATERAL DISTANCE OF THE REFERENCE LINE FROM THE LINE RAIL TO THE PERVIOUSLY ESTABLISHED PREDETERMINED LATERAL RELATION AT THE INTERMEDIATE STATION TO ESTABISH A SERIES OF ACTUAL VARIATIONS, PLOTTING A TWO DIMENSIONAL GRAPH WITH THE ACTUAL VARIATIONS AS ONE DIMENSION AND THE LONGITUDINAL STEPS AS THE OTHER, AVERAGING A CURVE THROUGH THE ACTUAL VARIATIONS, TAKEN AS A GROUP, TO ESTABLISH A SERIES OF DESIRED VARIATIONS, REPEATING THE STEP OF MOVING THE STATIONS, AS A GROUP, AROUND THE CURVE IN GENERALLY EQUAL STEPS, AND SHIFTING THE TRACK LATERALLY AT EACH STEP, WHERE NECESSARY, AT THE INTERMEDIATE STATION TO ESTABLISH THE DESIRED VARIATION FROM THE REFERENCE LINE ON THE TRACK. 